Two positive charges of magnitude $q$ are placed at the ends of a side $1$ of a square of side $2a$. Two negative charges of the same magnitude are kept at the other corners. Starting from rest, if a charge $Q$, moves from the middle of side $1$ to the centre of square, its kinetic energy at the centre of square is
Two positive charges of magnitude $q$ are placed at the ends of a side $1$ of a square of side $2a$. Two negative charges of the same magnitude are kept at the other corners. Starting from rest, if a charge $Q$, moves from the middle of side $1$ to the centre of square, its kinetic energy at the centre of square is
- [AIEEE 2011]
- A
$\frac{1}{{4\pi \,\,{\varepsilon_{0}}}}\,\frac{{2qQ}}{a}\,\left( {1\,\, - \,\frac{1}{{\sqrt 5 }}} \right)$
- B
$zero$
- C
$\frac{1}{{4\pi \,\,{\varepsilon_{0}}}}\,\frac{{2qQ}}{a}\,\,\left( {1\,\, + \,\,\frac{1}{{\sqrt 5 }}} \right)$
- D
$\frac{1}{{4\pi \,\,{ \varepsilon_{0}}}}\,\frac{{2qQ}}{a}\,\left( {1\,\, - \,\frac{2}{{\sqrt 5 }}} \right)$
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